1. Field of the Invention
The present invention relates to a method for processing a chamfering of an eyeglass lens or eyeglass lenses and an apparatus for processing the same, which are adapted to carry out a chamfering-processing simulation by inputting a chamfering width and a chamfering range based on a periphery of a lens shape of an eyeglass frame, by computing a chamfering trail after the chamfering and an edge end after the chamfering, and by displaying them.
The present invention also relates to a method for processing a chamfering of an eyeglass lens or eyeglass lenses and an apparatus for processing the same, which are configured to chamfer an edge surface in such a manner that a proportion between a width of a front bottom portion and a width of a back bottom portion centered on a mountain of a V shape or a groove is gradually changed, in the edge surface of the eyeglass lens on which the V shape or the groove engaging with an eyeglass frame or wire frame such as Nylol (registered trade mark) is processed.
The present invention relates to a method for processing a chamfering of an eyeglass or eyeglass lenses and an apparatus for processing the same, which are configured to chamfer by changing a chamfering width so that a width of a front bottom portion, a width of a back bottom portion and the chamfering width of an edge surface become optimum sizes.
2. Description of Related Art
Conventionally, there are known a lens grinding apparatus in which a periphery of a circular un-processed blank of an eyeglass lens or an un-processed lens is ground based on lens shape information (θi, ρi) in such a manner that the blank is formed into a lens shape of an eyeglass frame, a rimless frame and a wire frame such as NYLOL or the like, and an apparatus for processing a chamfering of an edge end of a peripheral edge of an eyeglass lens, after the blank is ground by the lens grinding apparatus, as disclosed in Japanese Patent Laid-Open Nos. H 10-225853, H10-225854, H10-225855, 2001-18154, 2001-18155, 2002-126983 and 2002-126985.
Moreover, conventionally, in the chamfering processing of the edge of the eyeglass lens, because it is desired to chamfer the edge so that the edge thickness is approximately constant throughout the minimum width to a middle width, and the middle width to the maximum width, the processing for chamfering in which the edge has a constant width visibly has been carried out by changing a width of the chamfering processing at any radius vector position of the lens shape of the eyeglass lens, as disclosed in the aforementioned patent publications.
Because eyeglasses in which an edge thickness of the eyeglasses attached to a frame is not appealing, have been requested to a wearer of the eyeglasses, when viewing the wearer attaching the eyeglasses from front, an apparatus for chamfering the edge surface, so that a width of each edge surface of the right and left eyeglass lenses after processing sees constantly, is disclosed in Japanese Patent Laid-Open No. 2001-157957.
On the other hand, in the eyeglass lenses on which V shapes and grooves are processed, an apparatus for processing capable of changing at any radius vector position of a lens shape of an eyeglass frame, widths of front and back bottom portions centered on bottom widths of edge surfaces, namely, widths of the front and back bottom portions centered on mountains of the V shapes and the grooves is disclosed in Japanese Patent laid-Open Nos. 2001-212741 and H7-186028, and Japanese Examined Patent Publication No. H5-41386.
However, in the conventional chamfering processing apparatuses, as described above, although an ear side of the eyeglass frame, in other words, the chamfering of an edge end of eyeglass lens at a portion of the frame far way from a nose pad (hereinafter, referred to as ear side), is carried out controllably by changing a width of chamfering, the processing for chamfering accurately the edge end at the side of the nose pad of the eyeglass frame, namely, a portion in the vicinity of the nose pad (hereinafter, referred to as node side) cannot be carried out controllably.
Therefore, because an edge thickness of the edge end at the nose side of each of the chamfered eyeglass lenses remains thick, the wearer feels the eyeglasses heavily and cannot wear the eyeglasses comfortably. Moreover, there is a case that the edge surfaces of the lenses abut with fittings for holding the nose pad, a worker of the eyeglasses carries out addition operations to the eyeglasses by hands. There has also raised a demand that a now how of a technical chamfering processing technology which has been carried out by the worker is realized by a processing apparatus and a fine processing can be carried out. If the eyeglass lens on which the V shape and the groove are formed is chamfered, when the width of the back bottom portion is less than that of the front bottom portion centering on the mountain of the V shape and the groove, there is a problem in the appearance because the back bottom portion or back edge portion after the eyeglass lenses having the V shapes is inserted in the eyeglass frame is small and therefore, the lenses see to project forwardly of the eyeglass frame. In case of the wire frame, because a portion of the frame is composed of a metal or cell, the lenses see to project from the frame from a relative position between the eyeglass lenses and the frame, similarly as the V shape processing, and therefore there is a problem in the appearance.
In case of the eyeglass lenses on which the groove is formed, the width of the back bottom portion is short, when the eyeglass lenses are inserted in the wire frame such as Nilol (registered trade mark), there is a fear that strength for a wire becomes low.
Furthermore, in the chamfering processing apparatus, the V shape processing apparatus and the groove processing apparatus, in the prior art as described above, because the bottom widths of the chamfered edge surfaces, in other words, the widths of the front and back bottom portions centered on the mountain of the V shape, the widths of the front and back bottom portions centered on the groove are not processed into balanced optimum sizes, in the processed eyeglass lenses on which the V shapes and groove are formed, in the eyeglasses that processed lenses are inserted in the eyeglass frame, the edge thickness throughout the entire periphery of each of the eyeglass lenses is appealing, a good appearance cannot be expected, and the strength for supporting the wire frame such as the Nylol (registered trade mark) is not sufficient.